Alternating-current track-circuit signaling.



I W. K. HOWE. ALTERNATING CURRENT TRACK CIRCUIT SIGNALING.

APPLICATION FILED SEPT. 30, 1911. 4

1,056,993, 1 Patented Mar. 25, 1913.

4 BKBETS-SHEET 1.

- WWI-M58858: I i nwmron I I 0% 7 W71 7441K 2 E 2 Z BY ATTORNEY W. K.HOWE. .ALTBRNATING CURRENT TRACK CIRCUIT SIGNALING.

Patented Mar. 25, 1913. I

APPLICATION FILED SEPT. 30,1911 1,056,993.

4 SHEETSSHEET 2.

W INVENTOR ATTORAIFV WITNESSES:

W. K. HOWE.

TRACK GIKCUET SIGNALING.

ALTERN ATING 0 URRE APPLICATION FILED SEPT. F10, 1911.

Eatented Mai. 25, 913.

t PIN i Milan xi! W. K. HOWE; I ALTERNATING CURRENT TRACK CIRCUITSIGNALING.

APPLICATION FILED SBPT.30,1911.

Patented Mar. 25, 1913.

4 SHEETS-*SHEET 4.

.i m II mw. 7v

INVENTOH ATTORIV WI TNE88E8: M

lilting joints used in track circuit signr ii'llln' 'lT/INTHROI K. HOWE,033 new SIGNAL COMPANY, 0 E

Application T0 and whom it may concern 5 Be it knownv that l, WINTHRoP ia citizen of the United States, of the city of Rochesteryin the coMonroe and State of New licrh; rented a new and useful Ethernet rentTrack-Circuit Signaling, of Wli following is e specification.

This invention relates to track e ncling and especially to alternating;track circuit signaling.

One object of this invention is the normal consun'iption of energy in.s. t circuit to a minimum;

Another object of this inventi duce the maximum energy consuin minimum.

As is well understood by those s ii the art, the greatest amountensupplied by the Well known 'trac former used in alternating current tcuit signaling when the transforme the track are practically shortcircthe presence of a train upon the tree. such point.

It is an object of this invention tere: the energy consumption undersuch so tions to a value much less than the norm consumption of energyby the rack circui A further object of this invention nullify theextremely bed results cause.

the short circuiting of the well know" and to thereby obtain what istech known as broken down joint projectio Insulating joints in tracksare n source of annoyance, but. as yet no u practical scheme of trackcircuit Without them has been thoroughly periec so that they must atpresent he endured. is necessary, however, to provide against dangercaused by the breaking down short circuiting of such joints. The dz.resulting from such breaking down in the fact that the electrical-energyin track circuit section is liable to falsely op ate the relay in thenext section. Such. on ation may result either in holding a, signaldanger when it should be at clear or holding a signal at clear when itsheu at danger. The first of these is tremely annoying and would causetll'l lay to traffic; the second is or such 2,

-' switclia operated by the signal controlling the track circuit sectionin advance so that in one po'- sition of said signal the pole changingswitch will be in such a position as to cause current to be fed to thetrack circuit section in the rear having a difference of phase onehundred eighty electrical degrees removed from the phase of the currentsupplied to the track circuit section when the said signal andconsequently the pole changing switch are in another position. Byemployinga relay which will assume a central position when no currentflows therethrough and which will close a contact on one side of thecenter when current of one phase relation flows therethrough and whichwill close a contact on the other side of the center when current of theother phase rela- 1 whether they are of like polarity or of un-' likepolarity when thejo-ints break down for either the relay of one section"or the current supply of the adjacent section will be short circuited,consequently, the relay in one section or the relay in 'the other willmove to the central position and cause a false danger signal, thusattracting immediate attention to the defect. It must be readily seenthat the method of transposing the connections from the current supplyto the track circuit in alternate sections would not provide for brokendown joints in a three position polarized relay scheme of signaling. Ifthe joints should break down there would be at times a current in theadj acent section of the proper polarity to actuate the relay to' causea false clear signal. The third method although applicable to a threeposition polarized relay scheme of signaling introduces othercomplications which at present it is not desired to introduce, in theway of a larger number of parts in the insulating joint. Although adiagonal bond scheme of broken down joint protection in a polarizedrelay track circuit system of signaling thus appears to be the .mostpracticable method to use, it has manifest disadvantages. Onedisadvantage lies'i'nthe fact that with a steam road system a path forany foreign current which may be present at any part of the line isformed, wliiclr'allows the current to flow unimpeded the full length ofthe line, and as at present most foreign currentis of the direct currenttype, and may fiow through the track relays, causing a magneticsaturation of the magnetic stator and so causing a slowing of the rateof movement of the rotor, it is necessary .vhen

diagonal bonds are used to so construct the relays that they are immuneto the effect of direct current, as for instance by the method fullyshown, described and claimed in the application of Oscar A. Boss andAnthon H. Vogt, Serial No. 593,673, filed November 22nd, 1910. Anotherditiiculty of greater moment is the fact that with road ballast having alow insulation resistance the leakage of current from one track circuitsection to another track circuit section in another track as on a doubletrack road may in wet weather amount to suiiicient to wrongly op eratethe track relay in the track to which the leakage current flows, andmight under extreme conditions cause a false clear signal, as such aconstruction increases the tendency for leakage.

Polarized track circuits have not only the difiiculties above mentioned,but also the diiiiculties incident to ordinary track circuits, to-wit: alarge normal energy consumption due to the fact that a resistance musthe placed in series with the track leads from the energy supply in orderto limit the current flow to a safe value when the track leads are shortcircuit-ed as by a train standing on the trackat the point ofconnection. As a-train may short circuit the track leads for aconsiderable length of time, a means must be provided to dissipate theheat generated in the resistance, consequently it has heretofore beennecessary to form such resistance into cast iron grids of anon-inductive construction and to place the same at some point close tothe track in a box, to which the outside air has free access, thusforming an undesired and sonic times unsightly obstruction on theright-ofway. Applicants invent-ion obviates the necessity forresistances and heat dissipating structures and so removes another ofthe objectionable features of alternating current track circuitsignaling. The use of a resistance in series with the track leads alsoobligesthe use of a higher electromotivc force than wouldptherwisc benecessary, in order to cause the necessary current to How in the trackcircuit to operate the relay, thus increasing the normal energyconsumption. As applicants invention limits the value of the maximumcurrent flow in the track circuit to far below the value which itattains in systems as installed, it allows the use of smaller conductingmembers between the energy supply and the track and so etfects a muchdesired economy of high priced material, and as a series of trackcircuit sections would consume very much less energy than presentsystems, the line wires from the'central stat-ion supplying energy toall of the track circuit sections could be much reduced in size therebyeffecting another economy. The generator at the corn tralstation couldalso be smaller and conmesses sequently much less erpensive in firstcost and to install and to operate. In order to explain the principle ofthe invention, and to describe the mode of operation and construction ofthe particular physical embodiment of the invention se-' 2 diagram,similar to Fig. 2, showing the systern as applied to a steam propelledroad. 4, is a diagrammatic view of a wireless automatic block si showsthe construction of one of the improved elements ot'my system, to-witrthe so called automatic reactance.

Upon the base 1 is fastened the M shaped member 2, composed of thinsheet iron laminae. The post 3 rigidly attached to the base' 1 has anupper bifurcated end through which extends a pivot pin 4- supporting alever 5, having on one end an adjustable weight 6 and having the otherend formed into a hook 7. The hook 7 passes through the eye of a rod 8,which is fastened to the center of'a ll shaped rod 9, thelower ends ofthe U shaped rod each being fastened to a plate of non-magnetic material10 having a central cut-away. portion' ll in order that the plate maypass over the middle limb of the M shaped memberii. A. coil of insulatedconducting wire 12 preferably made of copper is Wound about both limbsof the: U shaped member 9. and is supported by the plate lO, the ends ofthe coil'being attached to the binding posts 13 and 1A. If the coil 12,is connected in series-with a source of current of constantelectromotive force .and

an adjustable resistance, with the resistance so adjusted that not morethan a certain predetermined uantity of current flows through the coilthere will be no bodily movement of the coil, but if the quantity ofcurrent flowing through the poil is increased by cutting out resistance,the magnetic field produced by the current flowing in the coil 12 will,in its endeavor to flow through the path of least reluctance draw thecoil downward upon the middle limb of the M shaped member 2, overcomingthe torque produced by the weight 6 to hold it in its normal position asshown in Fig. l. A gradual removal of the resistance in series with thesupply of current and the coil 12, will cause the coil 12 to be drawnlower and lower upon the middle limoof the member al system. Fig. 1,-

2, but the downward movement is resisted by a greater and greater torqueexerted by the weight 6 as it is apparent that the weight 6 as it movesupwardly to a horizontal position exerts a greater and greater torquethis torque being proportional to the increasing torque of the coil1221s it is drawn down farther and farther upon the middle limb of themember 2. In practice the device is so designed, however, that a veryslight increase of current is required to start the coil 12 to movingdownward. As the coil moves downwardly upon the middle limb of themember 2, the reactance of the coil to alternating current is graduallyincreased. The increased reactance in the coil caused by its movementdownward upon the middle limb oil of the member 2 is a phenomenon wellunderstood by those versed. in the electrical art. As the reactancc ofthe coil increases, the some electromotive force which caused the normalpredetermined current to flow in the coil would necessarily cause lesscurrent to How in the coil, but if at the same time the adjustableresistance in series with the coil and the source of current weregraduallyw'nade less and less by the same amount, the same electromotiveforce which caused the normal predetermined quantity to flow through thecoil when in its upper position would still cause the same predeterminedamount of current to flow. It is to be observed that although thecurrent in the coil remains the same, the electromotive force across theterminals of the coil changes, for

I the drop of potential which formerly existed across the adjustableresistance has now been transferred across the terminals of theautoniatic re'actance thus largely increasing it. The increase in thereactance of the coil results in an increase in the apparent resistanceor impedance and also results in a dis placement of the phase of thecurrent so that it lags a greater or less extent behind theelectromotive force, therefore, the power factor of the circuit ischanged. In the case ot' thecoil just described, as the reactanceincreasesthe ohmic resistance of the 0011, re-

maining the same, the cosine of the angle as shown upon a system ofrectangular cotirdinates between an abscissa and a line representing thephase of the current when the coil is drawn downward to its greatestextent is much less than the cosine of the angle between the sameabscissa and the line representing the phase ofthe current when the coilis in the position as shown in Fig. 1, consequently, as the power factoris proportional to the cosine of such angles it is very much greaterwhen it is in the position as shown in Fig. 1,-and so closer to unity.It is also to be observed that as the power fac- 36idecreases,'unclersuch conditions the current is displaced in phase more and more as thecoil is drawn down upon the middle limb of the member 2 as the ohmicresistance remains constant but the rcactance ot' the coil changes.

' About the coil 19 is placed the copper annulus which is rigidlysimported in the fixed position shown in any approved manner. As it maybe possible that the power factor of the coil 12 when in the upperposition as shown in Fig. 1, is too low, it may in some cases benecessary to raise it which may be done by placing the copper annulus 15so that when the coil is in its upper'position it will be surrounded bythe annulus. Under such conditions an alternating cur rent flowing inthe coil 12 will generate a current in the annulus 15 which will reactin the well known manner upon the coil 12 to 'reduce its reactance andthus the ohmic resistance of the coil remaining; the same, increases thepower factor and as the power factor is' increased by a change in thereactance only. the current will be brought nearer in phase with theelectromotive force. in the great majority of cases it will probably beunnecessary to use the annulus 1:7, it being merely shown and describedto illustrate the most perfect embodiment of applicants invention makingit applicable to the most extreme condition.

Upon the front and back faces of the lid shaped member 2 the limitingstops it; and. 17 are adjustably mounted, being held in adjustedposition by screws as 18. r As the coil 12 is drawn lower and lower uponthe middle limb of the M shaped member '2, the reactance graduallyincl-uses and the power factor gradually decreases and the current isdisplaced in phase more and more as the coil is drawn down upon themiddle limb of the member 2 as heretofore pointed. out, but in somecases it may be undesirable to have the coil drawn entirely down uponthe middle limb of the member 2. thert'ore the ad justable stops 16 maybe used to prevent the coil mo'ving down too far, for in some cases itmay be advisable to prevent the great-a dec ease in the power factor ofthe circuit contztining, the coil 12 and tlnis prevent too great adisplacement of the phase of the current therein.

Referring toliig. 2, 10 and 20 designate the two rails of anelectrically propelled road, separated at intervals by the insulatinf}joints 21, thus forming blocks each of s which is governed by a. signalas 22 or 23 at the entrance tlmrcol A generator Qt is lo rated as iscustomary at one end of the line. one terminal of which is connected bythe Wire 25 to a central point of the winding upon the well known ironcore track reactance bond 26, the two ends of which are connected as at27 and 28in the two rails or" block at one end thereof. ill the otherend of the same block and at the beginning of the next adjacent blocksimilar iron core reactance bonds are placed connected in the usual andwell known manner and at the meeting points of all of the subsequentblocks reactance bonds are likewise connected, thus furnishing anunimpeded two rail return for propulsion current from the wheels 29 ofan electrically propelled car 30 to the source of current 24 at theterminal station. The motor 31 of the car 30 is con nectcd by oneterminal to the axle 32 upon which the wheels 29 are placed and the oLher terminal connected by means of the trolley pole 33 to the trolleywire 84- which is connected to one terminal of the generator 24: at theterminal station.

A. source 35 of alternating current is located at the central stationand is connected to the two line wire. 36 and 37 (attending the lengthof the track-way At suitable points the primary windings of thetransformers 3S and 39 are connected to the line wires. The secondarywinding 10 of the transformer 39 supplies the two position signal 29with current through the wire 41:1, point 42, contact arm 44' and wire4:5, and also supplies electrical energy LO one winding 1-6 of therelay. The relay of the well known polyphase type having two windings l6and t7 and a shell rotor 48 hearing the contact arm l4: whicln when therelay is energized is adapted to bear against the contact 42. Thesecondary winding 4-9 of transformer 38 through the wire 50 connects toone track rail 20 and by means of wire 51 connects to one end of coil 1upon the automatic reactance device and from the other end of the coil12 connects by means of wire 52 to the other rail 19 of the trackway,thus supplying en ergy to the track circuit. At the other end or theblock section thus supplied with energy, one wire 53 connects with onerail 19 and with one end of winding 4-7 of the relay and anotherwirehlconnects with the other track rail 20 and with the other end ofwindingr l7 oi the relay.

Aside from the automatic reactance device the system asshown in Fig. 2,is constructed and would operate exactly the same as the common and wellknown forms of alternating current block signaling systems, that is tosay the presence of a train upon either block section B r C would causein the well known manner the signal such as 22 or 23 governing theentrance to said block to move to the danger position. By the use of theautomatic r-eactancc, however, the various ol' jects herein bet-orestated are attained.

in ordinary systems in place of the coil 12 between wires 51 and .79 anon-inductive grid resistance is inserted so that in order to producethenccessary available drop of pontial across the terminals of wires 5?}and 5% at the points where they are connected coil 49 ofthetransformer38 than would otherwise be necessary, consequently, the

normal consumption of energy in such a track circuit is greater-thanoneinwhich the coil 12 is in series with wires 51 and 52, as the'co'il12 as constructed by applicant is of a great deal lessohm'ic resistancethan the non-inductive grids as ordinarily used,

therefore, the normal consumption of energy,

bya trackcircuit section is decreased.

As' the purpose of the non-inductive grid resistance is to limit-the'amou'nt' ofcurrent I which may flow when the wheels and axles ofa carbridge the terminals of wires 50 and 52 and as at; times' a car mayremain -in such a position for a great lengtlrof time, the

resistance grids must be of a;size to properly limit the. currentand atthe same time be so constructed and installed as to dissi- 'patethe heatgenerated by the flow of current through them under the most adverseconditions, at the same time,their resistance must'be of as low apraticablevalue as possible in order to, decrease as much as possiblethe normal energy'consumption of a track e rcrut-sectronQ It lsnipracticable to so design a non-Inductive grid resistance that. theamount of "current flowing when the terminals of wire E50 and 52 areshort circuited by. a trainis'ho greaterthan the amount of. currentflowing when no train is prsentuponthe track circuitsection. ,fln factthere is an enormous (inference-between; the amount of currentflowingunder normal conditions-and the amount flowing upon the short--circuiting ofthe -wires 50 and 52 so that the consumption of currentby a track circuit section 'under abnormal conditions is I very great Bythe insertion of the'automatic reactance inseries with wires 51 and 52.the presence of a train across the terminaisof wires --and 52 causes thecoil 12 to be; drawn down upon the middle limb of themei'nberfl, asshown in Figs. 2, 3 and 4,

and-as it is} drawn down upon'the member 'L2- the impedance of the coil12 is increased and the coil-l2jmay be so -designed by principles wellknown to electrical engineers .that the current flowing through coil 12will be the same whether a train is present, short tcircuiting theterminals of wires 50 and 52 or whether no train is'present, the trainand the track rails-taking the-place of the adjustable resistanceheretofore. described in connection with the-coil. As soon as a trainwhich has short circuited the terminals of wires 50 and 52 passes on,the weight 6 re- Qeo turns the coil to its initial position.

As thecoil 46 upon the relay is connected directly,- to the secondary 40of, the transformer39 and as it is wound upon the magnetic stator, of.the motor, it is as'ordinarily constructed highly reactive andconsequently the power factor is low and the current is displaced inphase from the-electromotive force by a considerable electrical angle.In order to get good operation of the relay it is therefore necessarythat the current flowing' throughwinding 47 of the relay be dis. placedas little as possible in phase from the electromotive force. With theconnections from the secondary 49 of the transformer 38 throughtheautomatic reactance 12 to the track-rails 19 and 20 as herein shown, thecircuit containing winding 47 has a high power factor. This is sobecause the ohmic resistance of coil .47 is a very small fraction of theohmic resistance of coil 46 and because the reacta'nce in the circuitincluding winding 47 is both very much less than the reactance in thecircuit including winding 4:6,- and the circuit including the winding 47is furthermorehighly resistive. The current flowing through winding 47is therefore more nearly in phase wit-h the electromotive force. Byreason of such facts a ood difference of base between currents inwindings 46 and 47 is maintained thereby resulting in a good torque inthe relay. \Vith the arrangements and constructions as shown by Fig. 2if the insulating joints 21r-should become siort circuited a currentwould flow from the rails of one section to the; rails of thenextsection and so through the track winding of the relay. It must bereadily understood that an operation of the relay would result, if thecurrent thereby reaching thetrack winding of the relay was displaced inphase, from the current flowing in the local winding of the relay as 46.As-heretofore pointed out, an operation of the relay under suchconditions is objectionable and in some cases absolutely dangerous andheretofore, in order to provide against such difiiculty as alreadypointed out, connections from the line wires to the track from the.supply of energy have been transposed in adjacent sections thus causingan operation of the relay under such conditions of broken'downinsulating joints that will result in a danger signal not in a clearsignal. As' heretofore pointed out such a method is not applicable tothe so-called alternating current polarized track circuit and recoursehas been had to the diagonal bond heretofore mentioned but the actancedevice exactly as does the presence of a train short circuiting itsterminals so that the movable coil thereof is drawn down upon the middlelimb of the iron member, the reactance of the coil is largely increasedand consequently the current flowing there through is largely displacedin phase from that of the electromotive force so as to lag considerablybehind the same. As has already been pointed out the current which iscaused to flow through the track winding of the relay in order toproduce a good rotation of the relay is displaced very slightly in phasefrom the electromotive force, consequently the current which flows tothe track phase of a relay from an adjacent section when the jointsbreak down, does I not have the proper phase relation as re gards thecurrent flowing in the local phase of the relay to produce the rotation,for,

the current flowing through-the track winding of the relay, under suchconditions is or can be made to have the same phase displacement fromthe eleetromotive force that the current flowing in the local winding ofthe relay has.

In Fig. 4 has been shown a three position automatic signal systememploying no line wires, that is, a system ordinarily known as awireless system. In its broad features it differs from the'system asshown in Fig. 2 merely by the means used to obtain the third position ofthe signal, to-wit: the pole changing switch designated generally by S.This switch is inserted in the leads from the track transformer and theautomatic reactance device to the track and is actuated by the movementof the signal blade, so that when the si al blade is in the full clearor90 position the switch will make the same contacts that it is makingas shown at S, but when the signal blade moves below the 45 or cautionposition, the switch will make the contacts as shown at S. Consideringthat at a certain instant positive current starts from the right handend of transformer 38 in section A, then the current will flow by meansof wire 50, arm 55, contact 56, wires 57 and 58 to the lower track rail20, and the return current will flow from track rail 19, through wire59, contact 60, arm 61,

wire 52, reactance coil 12, and wire 51 to the from that of switch S,on' account of the fact that the signal .23 has its blade at the dangerposition, but if the switch had not been moved but were in the sameposition as switch S, connected with section A, then the lower railinstead of being of positive I polarity would be of negative polarity.The polarity of the rails with the parts as shown is indicated by theusual polarity signs at the connections of the wires 58 and 59 to therails 19 and 20. The polarity of the rails in section C, with the switchS as indicated, will be the same as that in section A. It must bereadily seen, that the polarity 0f the rails in adjacent sections withall signals at clear is reversed so that abutting rail ends separated byan insulating end post will beof different polarity throughout thesystem, consequently any breaking down of the joints, while all signalsare at clear, would act upon the relay exactly as does thebreaking downof the insulating joints in the case of a system connected as is shownby Fig. 2. Even if by direction opposite to that which would cause thesignal to go to the clear position and so such a movement could onlycause the signal to move to the 45 or caution position. The circuit inwhich current flows to cause the signal to move to the 90 posi tion isas follows: secondary 40 of transformer 39, wire 41, signal mechanismwire 63, relay point 42, relay contact bar 44, wire 45 to the otherterminal of the secondary of the transformer. current flows for the 45position. is wire 41, connected to the secondary 40 of the transformer39, signal mechanism wires 64 and 65, e'onta t point 66, contact bar 44,and wire 45 to the oth r terminal of the transformer. It will beobserved that connection is made to wire 64 and to the negative terminalof the transformer when the contact arm 44 is in a position to causecur- .rent to flow through the circuit to move the signal to the fullclear position. This is the The circuit in which L censee ing the signalblade from the zero or danger when the signal blade is in the zero ordanger position and as soon as the connection were made to move thesignal blade to the position, no movement at all of the signal bladewould take place as it must on account of the construction of theoperating mechanism be first moved to the 45 position before being movedthereafter to the full clear position by the current flowing in the fullclear circuit. A car 30 is shown upon the rails of section C,consequently current is shunted from the track winding oi? the relay andthe contact arm 44 moves to the central or neutral position and in sodoing, breaks both the caution circuit and the full clear circuit, sothat the signal moves to the danger position as shown, and also movesthe pole changing switch S to the position as shown, reversing thepolarity of the current ordinarily supplied to the track section B,consequently moving the Contact arm 44: from its normal position fromcontact with contact points 42 and 67 to n position in contact withcontact point (36 as shown, thus causing the signal blade attached tosignal 22 to move to the 4-5? or caution position as shown. Withthe'signal 22 at the cantion or 45 position. caused by the movement ofthe pole changing switch S the polarities of the abutting rails at thein sulating joint at signal 22 will be the same, consequently, theoccurrence of a broken down joint at such a time would not result in afull clear signal, for even if the cur rent passing through theautomatic reach ance device in section A. were out of phase with thecurrent supplied to the local wind ing of the track relay in section B,any movement which tool; place would be in the same direction as thatcaused by the current in the section itself. If the insulating jointbetween sections B and (l were broken down and the phase of the currentpassing through the automatic reactance device connected to section Bhad not beenexactly balanced with the phase of the current,tlowingthrough the local winding of the relay' in section C and enoughmovement of the contact bar l l of the relay connected to C had beencaused to complete the circuit for the 45 indication, then upon theapproach of a train, the current would all he shunted through the wheelsand m of the train and the relay attached to the rrils of section Gwould be delinergized and the "ignal would go to the danger position and.ir t train had passed the insulating joint and gone i it did upon therails of section C, the signal ivould still remain at danger, foralthough the phase of the current supplied to section B through theautomatic reactance device might be under unusual conditions slightlydisplaced from the current supplied to the local Winding of the relay C,it would never be so largelydisplaced that it would be able to causesufficient movement of the contact bar of the relay in section C toclose the contacts after the relay had once been brought to rest, andespeciallyavhile a shunt was present, caused by the presence of a carupon the rails to which it is attached Whenever the insulating jointsbreak down between two sections as between sections B and C with notrain present, the signal governing the advancesection as 23*will beplaced to danger and at the same time the signal governing the rearsection as 22 will, also be placed at danger for the path of lowresistance furnished to the current from the automatic reactance device12,connected to section B -causes the coil 12 to be drawn down so far,upon the middle limb of the member 2 andthe reactance of the coilthereby so largely increased, that the phase of the current supplied tothe track winding of the *relay connected to section B is so largelydisplaced from normal and ap proaches so closely to the phase of thecurrent supplied to the local winding of the relay connected to sectionB that suiticient torque is not exerted upon the rotor of the relay tohold the contact bar it in the very extreme position. Even if thecurrent supplied to section B should teach the track winding of therelay connected to section G and even it it should he disolaced in phasesutticiently to operate the relay, no dangerous results could flow, forthe direction in which'thc contact bar 44 would be moved, would betoward the central or neutral position as the polarities would beopposite in the two sections,.consmpiently, the i to danger, butlas soonit did no to danger the pole Chang switch S5 would he changed to theEJOSlLJdll shot 4, thereby reversing the polarity c rent supplied. thera the current would ilo: to the relay co a direction to c the 45 or so7 again revs ac current 2 g i the total r a: of the sig' being I x fromthe degree position to. the sition ltis to be observed the "oplicationof the automatic react ace device to'a poial would hing, so that the sinal l'arized track circuit, just as in the of its application to anunpolariacd track circuit, does not necessitate any connections whichare at any time idlc in the normal working of the system, consequently apoor connect-ion or e broken connection wlich would d stroy the eiiectof the protective apparatus would also so disturb the normal operationof the system that the signal atfcctcd thereby, which would under brokendown insulated joint conditions be affected by the automatic reactnnce 1evice, would be moved to the danger position Although applicant hasherein shown and described his new and useful means in connection withwhat are or inarily tern d two rui track 'cirt it is obvious to thoseski t the new and useful means describe by "int are equally applicableto any form. of rail circuits and applicant considers that thezunilication of his novel, and useful means to the so-called single railtrack circuits, is well within his invention; i

As the power .actor of the circuit i :lud ing the auton'iatic reactanccdevice do creased by short circuiting the terminals of its coih there isno large increase of current flow in broken down joint conditionsosthere is in systems as ordarily installed, therefore, another big(llfilil upon the capacity or". the ccntrzl station and or"- the alincurrent ene ator is climiimtcd.

I this etem ol lies in the tact *rned in the the wires tact inorriuallyn so relied upon method of protcclici'i are moi and c micctionswhich must he dcr for the syslen. to ope that if any of tilt connci' itosecure ln'oli'cdown not intact the condi is inunc fol nonicd by thefailure oi the '1 to operate as it 'cndcd to i'i rmully Upiill} I vcllon that inc shamiddle limb ol "once would be in power fa t r uit would1h nccomc so low hat s mowing in such HV-lllli woulu be he n 5o d nphase 1 with the current in winding oi the rclcy l, but it migl l;l "(lstill furllui so 'liEPi, :1 rotatioi relay ocrur in a direction to .i.iu ordcr lo avoid this dilliculty the-ad iusiublestops can be so phurcdthat tho p wcr tractor oi the circuit containing the coil l9 and thetrack winding ot the relay in the adjacent section.

is never decreased to point below the power factor of the currentcontaining the n my local winding of the relay in the adjacent Althoughapplicant has herein shown and described a. ccppc' annulus as beingplaced about the coil 12 of the automatic rcuctancc device, it mustv bedistinctly understood that such is not a necessary part of applicantsinvention and that the same would only he used under extreme conditionswhen, for instance. the phase of the (summit flowing to the track phaseof the relay under normal conditions displaced at too great an elemlriral imglc to the phase of the electromolivc force.

Although applicant has hcrcin shown and described his invention asapplied to an automatic block signal system, applicant wishes it to beunderstood lha t the invention is by no means limited to such a system,for the lninciplc underlying the invention is applicable in ciimucclionwith track circuit sci-lions used for any purpose.

llaving explained the principle of my invention and described theconstruction and mode of operation of a part icular physial embodimentthereof, what l clailn as new and desire to secure by Letters Patent is:

l. in a. system oi track circuit signaling: a source of alternatingcurrcnt: a lruckway composed in rails: insulating joints in the rails atintervals forming sections; a trans lati :g device in each sectionhaving two u'iudiu" connections from onc of the wimlin i, o the sourceo'l' current; courier .i'om the other winding to the lraclt ls: con;\ullhllr between the source of cur nt and the rails in cuch section; anda device inserted in said last numcd conucc lions adapted to change thephase ol current flowing lhcrcthrmigh upon a breaking down oi theinsulating joints between two abutting; sci-lion and the completion of acircuit from the connections from the source 0t alternating current inone section through lhc winding 01" the translating dcvicc of thc zuliaccnl section connected to. the track rails, the change bcing such thatthe current will have a phase dill'crcnt from that, of the current whichproperly flows in the adjacent section, so that the improper flow ofcurrent will not cause the same operation of the 2. In 2 system of truckcirmit Sif a source of alterna mg current a lnsulatnw 5 composed of milsrzuls at lntervuls for translating device in each sicv tions between thetranslating w v T1 1 v Flu.

